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Topic: JSB 25.39 and 33.95 velocities (Read 466 times))

Hi guys , I have got on order some of the redesigned 25.39 and 33.95 jsb pellets anybody got a BC for the pellets as they seem to vary from forum to forum , the rifle is a bt65 .22 cal which has a huma reg with a .25 cal plenum , has anybody got velocity figures for these pellets to save a lot of wasted pellets .Here in the UK it was a job to find the redesigned 25.39 so ordered both from Krale in Holland it was the same in postage as the cost of the pellets so expensive Ö..I see Teds holdover used a .25 cal 34grn at 860 with good results and wondered if the .22 with the 33.95 at that speed or 900 ish would work .

I use .0460 b.c. for mk11 .0410 for mkl1's and .0360 for the 25.39 grain jsb's. I find it accurate enough for 150 yards, but corlolis effect will play on a pellet in the air that long. .75 of a second in the air, thats about 2" high shooting west 2" low shooting east. North and south also throw it off, to the shooters right about 2".

Correct .22 pellets . There was an article on here were someone tried the 25.39grn the redesigned and the other one's but I couldn't find the article to get an idea of the velocities he used , My reference to Ted's Holdover was he used a .25 but with a lower velocity of 870 fps for better stability and wondered if the same velocity range would work with the .22 pellets .

It has been a while, but I tried shooting the JSB 33.9 grain pellets out of my 50 FPE Daystate Air Ranger. I could just get to 50 FPE with them, which is only 815 fps.

Anyways, I ran chrony tests at both the muzzle and at 20 yards indoors, and using the average fps data from those tests, I calculated a BC of 0.057 from that gun at that speed over that distance. Your mileage may vary, but that is what I got - a very impressive BC indeed . . .

I tried the 25.4s, but they shot horribly - the only pellet not to shoot well out of that gun! They did Chrony at 920 fps with the same set up, but I never bothered to do the test at distance so I did not calculate a BC for that pellet.

With my slightly modified SPA M11, I have run the 33.9 's at 965-970 fps with some impressive results, (lets call it Minute of Squirrel Head), out to 150 yds. That's just touching on 70 FPE ! ! ! Not too bad for .22 cal ! ! !

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Thanks guy's they should be here Monday so looking forward to getting time to see what they can do , current running 21.14 at 930 and very accurate but just need to see if there is more to be had , pushing the envelope as they say .

I've had great results with the Hatsan barrels shooting the 25.39 redesigned anywhere from 880fps all the way up to 975 fps. I usually tune for around 950fps with those, because I only use them for a specific critter busting purpose I never shot the 34grain much, but most people with Hatsans that I know, say they shoot best around 850fps(give or take) in their guns.